The Sour Cherry or Morello Cherry, (Prunus cerasus) is a species of Prunus in the subgenus Cerasus (cherries), native to much of Europe and southwest Asia. It is closely related to the Wild Cherry (P. avium) from which sweet cherries derive, but has a fruit which is more acidic, and so is useful primarily for culinary purposes.

The tree is smaller than the Wild Cherry, growing up to 4-10 m tall, and has twiggy branches, whilst the crimson to black fruit is borne on shorter stalks.